print(len(dir(__builtins__)))

# 类型转换
print(int("-123"))
print(int("12F1", 16))  # 十六进制输出格式
print(float("123.12"))
print(str(123))
print(bool(1))
print(list([1, 2, 4, 5]))

# 数学运算
print(abs(-1))
print(round(123.452131311, 2))  # 保留2位小数四舍五入

# print(self, *args, sep=' ', end='\n', file=None)
print("hello word", "nice to meet you", "long time no see", sep="**", end="end")
